Angle of arrival (AOA) sensors generally include an aperture that collects incident light, such as the light from a laser designator or laser illuminator that is back scattered from an object. The aperture projects an illuminated spot onto a 4-quadrant detector. The size of the illuminated spot is slightly larger than the size of one quadrant of the detector, so that at least two quadrants are illuminated. Each detector quadrant produces an output current. The values of the four output currents are then processed to determine the location of the center or the centroid of the illuminated spot and thus the angle of arrival of the incident light relative to the common axis of the aperture and detector.